Asymmetric dimethylarginine is not a marker of arterial damage in children with glomerular kidney diseases

Can Surrogate Markers Help Define Cardiovascular Disease in Youth?

PURPOSE OF REVIEW

Non-invasive measurements such as arterial stiffness serve as proxy surrogates for detection of early atherosclerosis and ASCVD risk stratification. These surrogate measurements are influenced by age, gender, and ethnicity and affected by the physiological changes of puberty and somatic growth in children and adolescents.

RECENT FINDINGS

There is no consensus of the ideal method to measure surrogate markers in youth (< 18 years of age), nor standardized imaging protocols for youth. Currently, pediatric normative data are available but not generalizable. In this review, we provide rationale on how currently used surrogates can help identify subclinical atherosclerosis in youth and affirm their role in identifying youth at risk for premature CVD.

Arterial stiffness in children with primary hypertension is related to subclinical inflammation

Introduction

The immune system can trigger an inflammatory process leading to blood pressure elevation and arterial damage. The aim of the study was to assess the relation between subclinical inflammation and arterial damage in pediatric patients with primary hypertension (PH) and to establish the usefulness of neutrophil-to-lymphocyte (NLR) and platelet-to-lymphocyte (PLR) ratios, and mean platelet volume (MPV) as markers of arterial damage in these subjects.

Material and methods

In 119 children with PH (14.94 ±2.76 years) and 45 healthy children (14.91 ±2.69 years) we analyzed markers of subclinical inflammation (NLR, PLR, MPV), clinical and biochemical parameters, office blood pressure, ambulatory blood pressure monitoring (ABPM), central blood pressure, aortic pulse wave velocity (aPWV), augmentation index corrected for heart rates 75 (AIx75HR), carotid intima media thickness (cIMT), and common carotid artery stiffness (E-tracking).

Results

Children with PH were characterized by significantly higher neutrophil (3.9 ±1.7 vs. 3.0 ±1.0 [1000/µl], p < 0.001) and platelet counts (271.9 ±62.3 vs. 250.3 ±60.3 [1000/µl], p = 0.047), NLR (1.9 ±1.5 vs. 1.3 ±0.4, p = 0.010), PLR (131.4 ±41.9 vs. 114.7 ±37.6, p = 0.020), aPWV (5.36 ±0.88 vs. 4.88 ±0.92 m/s, p = 0.004), and cIMT (0.46 ±0.07 vs. 0.43 ±0.07 mm, p = 0.002) compared to healthy children. In PH children NLR correlated positively (p < 0.05) with: systolic, diastolic and mean blood pressure in ABPM (r = 0.243, r = 0.216, r = 0.251), aPWV [m/s] (r = 0.241), aPWV Z-score (r = 0.204), and common carotid artery PWVbeta [m/s] (r = 0.202).

Conclusions

There is a link between arterial stiffness and subclinical inflammation in pediatric patients with primary hypertension. Neutrophil-to-lymphocyte ratio may serve as a promising marker of arterial stiffness in pediatric patients affected by primary hypertension.

Asymmetric Dimethylarginine (ADMA) in Pediatric Renal Diseases: From Pathophysiological Phenomenon to Clinical Biomarker and Beyond

Asymmetric dimethylarginine (ADMA), an endogenous nitric oxide (NO) synthase inhibitor, inhibits NO synthesis and contributes to the pathogenesis of many human diseases. In adults, ADMA has been identified as a biomarker for chronic kidney disease (CKD) progression and cardiovascular risk. However, little attention is given to translating the adult experience into the pediatric clinical setting. In the current review, we summarize circulating and urinary ADMA reported thus far in clinical studies relating to kidney disease in children and adolescents, as well as systematize the knowledge on pathophysiological role of ADMA in the kidneys. The aim of this review is also to show the various analytical methods for measuring ADMA and the issues tht need to be addressed before transforming to clinical practice in pediatric medicine. The last task is to suggest that ADMA may not only be suitable as a diagnostic or prognostic biomarker, but also a promising therapeutic strategy to treat pediatric kidney disease in the future.

Serum Periostin as a Potential Biomarker in Pediatric Patients with Primary Hypertension

Experimental studies suggest that periostin is involved in tissue repair and remodeling. The study aimed to evaluate serum periostin concentration as potential biomarker in pediatric patients with primary hypertension (PH). We measured serum periostin, blood pressure, arterial damage, biochemical, and clinical data in 50 children with PH and 20 age-matched healthy controls. In univariate analysis, children with PH had significantly lower serum periostin compared to healthy peers (35.42 ± 10.43 vs. 42.16 ± 12.82 [ng/mL], p = 0.038). In the entire group of 70 children serum periostin concentration correlated negatively with peripheral, central, and ambulatory blood pressure, as well as with aortic pulse wave velocity (aPWV). In multivariate analysis, periostin level significantly correlated with age (β = -0.614, [95% confidence interval (CI), -0.831--0.398]), uric acid (β = 0.328, [95%CI, 0.124-0.533]), body mass index (BMI) Z-score (β = -0.293, [95%CI, -0.492--0.095]), high-density lipoprotein (HDL)-cholesterol (β = 0.235, [95%CI, 0.054-0.416]), and triglycerides (β = -0.198, [95%CI, -0.394--0.002]). Neither the presence of hypertension nor blood pressure and aPWV influenced periostin level. To conclude, the role of serum periostin as a biomarker of elevated blood pressure and arterial damage in pediatric patients with primary hypertension is yet to be unmasked. Age, body mass index, uric acid, and lipid concentrations are key factors influencing periostin level in pediatric patients.